Vaginal cells of smokers are more resistant to human papillomavirus infection than that of non-smokers.

To evaluate effect of HPV and smoking on DNA double-strand breaks in vaginal samples, vaginal specimens collected from participants (n=76) were classified based on HPV and smoking status, and DNA double-strand breaks measured using comet assay. Mean tail length (31.2±18.7μm) and tail moment (2.4±2.8 arbitrary units) for HPV-positive patients were lower (p<0.001) compared with HPV-negative patients (61.7±22.6μm; 8.7±4.9AU). Never-smokers were found to have a higher level (p<0.001) of double-strand breaks (57.7±24.5μm, 7.5±5.5AU) compared with ever smokers (35.3±21.9μm; 3.4±3.7AU). Among HPV infected patients, never-smokers have more double-strand breaks compared to smokers (p<0.001) which correlated with age (p<0.001). Highly differentiated vaginal epithelium may be resistant to DNA damage associated with HPV infection and smoking, which may be attributed to adoptive survival mechanisms of vaginal epithelium.